In practice very many methods are know to send digital data, particularly digital data through a network. An example are digital data that are sent through the internet, but also digital telephone signals, such as for instance in case of cordless GSM telephones.
In practice also various methods and devices are known for inverse multiplexing digital data.
The data are sent in the form. of data packets via a medium. This can take place via a physical cabling in for instance copper or glass fibre, or cordless, for instance via infrared or radio waves.
Because the capacity of data transfer, often coupled to bandwidth, of the media over which the data are sent is mostly too small, the data are often compacted. However, this has often appeared not to be sufficient.
Additionally many of these methods are aimed at optimising the data transfer between two computers. Moreover, many techniques require an overhead, and are not always as robust regarding the errors or failures of lines and other malfunctions.